Persia is modern day Iran

Dan 10 12-14"Then he said,"don't be frightened Daniel ,for your request has been heard in heaven and was answered the very first day you began to fast before the Lord and pray for understanding,that very day i was sent here to meet you.But for twenty one days the mighty evil spirit who overrules the kingdom of persia blocked my way.Then Michael,one of the top officers of the heavenly army ,came to help me,so that i was able to break through these spirit rulers of persia.Now i am here to tell you what will happen to your people ,the JEWs,at the end times-for the fulfillment of this prophesy is many years away."

(the living bible)